Substantial changes have occurred in the telecommunication industry over approximately the past decade. These changes have been driven, in part, by the dominant technology that underlies long distance communication links transitioning away from time division multiplexing (TDM) to packet networks. Internet traffic, videoconference calls, and even everyday, audio phone calls are often conveyed as streams of digital information broken into small packets of fixed size. Each packet contains information on the destination network device to which the packet is to be sent. The packets travel over communication links within packet networks interspersed in no particular order with packets from other independent calls or sessions.
Today, packet networks often convey telecommunication calls, including every day, two party voice calls, audio conferences, and videoconference sessions. Such calls may pass though a number of network devices as they travel between the end nodes of the call, that is, between the telephones, videoconference stations, or voicemail systems involved in the call.
Packet networks may have decentralized architectures that provide multiple communication links from any particular end node to any other end node. Decentralization and redundant links within packet network is generally desirable in that it helps ensure the reliability of the telecommunication system if, for example, some of the network devices fail or cause loss or errors during transmission.
Telecommunication suppliers may allow customers to make an, unlimited number of calls within a specified service area for a fixed monthly access price. Nevertheless, per minute billing is still common, and even fixed monthly rate plans may charge by the minute for calls outside of the specified service area, for example, for calls to destinations outside the local calling area, or outside the United States.
When a telecommunication call is routed over packet networks among various network devices, there may be no single network device that has access to all of the details of the call that are relevant to billing for that call. This can be especially problematic where different network devices handling a call are manufactured or operated by different companies, or where different network devices use different communication protocols. Each type of network device may produce call data with different characteristics, for example, data in different data formats, data represented with different data types, or data using different data storage and handling schemes.
Call data is often recorded in the form of call records. Call records may be generated by various types of network devices, for example, switches or gateways. Call records may also be generated at various points during a call, for example, the beginning or the end of the call. Various details may be included in the various types of call records including time, date, call duration, number dialed, caller ID information, extension, line or trunk location, call completion status, etc. Call records can be used for usage verification, billing, network management, provisioning, and other purposes.
However, the type, format and handling of call records is typically different in network devices of different types. Thus, it is often difficult to process call records to properly determine the characteristics of a telecommunication call.